This invention relates to a so-called heel plate arrangement for a cross country ski boot which permits the heel plate of the boot to move vertically relative to the ski and at the same time restricts lateral movement of the boot relative to the ski when the heel is resting on the ski and, more particularly, to such an arrangement which is designed to be effective for downhill maneuvering.
Cross country skiing requires techniques which are significantly different from those utilized in downhill skiing where the ski boot is rigidly fastened to the ski. The cross country skier normally fastens the front portion of his boot to the ski in such a way that the front is a pivot point while the heel is free to move vertically up and down. The vertical freedom of movement of the heel allows for more effective movement on uphill and level terrain. However, when skiing downhill lateral movement of the heel should be restricted so that the skier can turn effectively.
Various arrangements have been proposed and utilized in order to provide this type of connection between the heel of the ski boot and the ski. A typical arrangement is shown in U.S. Pat. No. 3,775,866 to Marker where a pin mounted on the ski is adapted to mate with an opening located in the bottom surface of the heel. This arrangement is unsatisfactory because snow tends to become packed in the opening which significantly reduces the ability of the pin to restrain lateral movement of the heel during sharp turns. A similar arrangement is shown in Austrian Pat. No. 61,783 where an inverted V-shaped member in connected to the ski instead of a pin.
Other types of heel engagement arrangements are shown in U.S. Pat. No. 2,498,085 and Norwegian Pat. No. 77,799 where a groove is located in the heel of the ski boot which can alternately be permanently engaged to the ski or provide a sliding engagement. However, these devices require active intervention by the skier in order to achieve vertical freedom of movement. Further, the opening in the heel has a tendency to fill with snow and reduce the effectiveness of the arrangement.
Another arrangement is shown in U.S. Pat. No. 3,618,233 where the rear edge of the ski boot heel is vertically grooved to cooperate with a flat, tapered, upstanding metal post attached to the ski. This arrangement is designed primarily to locate the ski boot relative to the ski during striding or level terrain cross-country skiing and has little if any ability to prevent overriding or disengagement of the ski boot heel during downhill maneuvering. With the notch located in the heel, in order to provide for sufficient resistance against lateral movement the heel would have to be so radically notched as to destroy or seriously impair its function. Further, in order to provide for any reasonable resistance against wear the heel would be required to be reinforced as shown in the patent.